Horse race fixers have long used “ringers” to pull off betting coups, but a new kind of ringer -- genetic duplicates cloned from the DNA of yesterday’s champions -- could soon be barreling around a racetrack near you if two Texas horsemen have their way.

In a lawsuit set for trial Tuesday in Texas, the horsemen are asking a federal judge to force the American Quarter Horse Association to register cloned horses and their offspring, arguing that it is violating antitrust law by refusing to do so.

A decision favoring the plaintiffs -- Jason Abraham of Canadian, Texas, and Gregg Veneklasen of Amarillo -- could clear the way for clones to compete in sanctioned quarter horse races at scores of racetracks in the U.S. and elsewhere. The clones would in many cases be genetic duplicates of quarter horse royalty like Tailor Fit, a two-time world champion -- and a gelding -- who now has a young copy named Pure Tailor Fit.

Debate is raging over how cloning could impact the American Quarter Horse -- an agile horse bred for speed rather than stamina. Quarter horse racing, which generated more than $300 million in wagering at U.S. racetracks in 2012, is the third most popular form of equine racing after thoroughbred and standardbred racing, and quarter horses also are prized in rodeo events for their athleticisim. Stallions like Pure Taylor Fit can bring in $1,500 or more per mating.

Whether or not the pro-cloning argument carries the day in U.S. District Court for the Northern District of Texas in Amarillo, equine clones will be appearing before the year is out in other equine sporting venues -- including non-breed specific rodeo competitions like barrel racing and reining, polo matches and equestrian events leading up to the 2014 Olympics, according to backers of the technology.

Cloning critics say allowing the procedure could concentrate the genetic pool and undermine efforts to improve the breed.

In a statement on its website, the AQHA says it intends to vigorously defend its ban, arguing that as a voluntary private association it has the right to set rules favored by a majority and citing a recent survey that found 86 percent of its members oppose cloning.

It also said that accepting clones would render useless its use of DNA to track horses’ lineage, because clones would possess the same DNA as the original.

“Clones don't have parents,” it said. “Cloning is not breeding.”

Researchers clone animals by transplanting the genetic information from a cell in a donor animal -- either dead or alive -- into an unfertilized egg cell whose genetic information has been destroyed or physically removed. In the case of horses, that egg is then implanted into a surrogate mare, where -- if everything goes smoothly -- it develops into a viable foal.

Commercial cloning of farm animals like cattle and pigs is increasing, but questions remain about the technology.

The Roslyn Institute of Edinburgh, Scotland, which created the world’s first cloned animal -- Dolly the sheep -- in 1996, “no longer undertakes research related to cloning of animals” and notes that some physical abnormalities have been observed in clones.

“Cloned animals have, in some cases, displayed growth defects although exactly why is not known,” it says on its website. “The growth defects are probably a result of the in-vitro culture conditions and due to changes in chromatin in the nucleus, but further research would be required to fully understand this.”

But the potential for defects isn’t what riles many quarter horse breeders and owners about the lawsuit, which seeks damages and an injunction that would prevent the AQHA from barring clones from the official breed registry.

A former AQHA president made “intimidating remarks and references to the immorality of cloning” and vowed that the “AQHA will allow cloning over my dead body” at a meeting of the organization last year, according to the complaint.

'An uneducated voice'

Veneklasen, who is both a plaintiff in the lawsuit and a veterinarian who has participated in the cloning of many horses, argues that a few influential AQHA members have swayed opinion against the technology and kept a proposal to drop the cloning ban from being considered.

“The loud voice is an uneducated voice and an opinionated voice,” he said. “And four or five voices are all that people are getting to hear.”

Veneklasen argues cloning would strengthen the quarter horse breed by re-introducing genetics from past champions who are deceased or otherwise unable to breed, possibly because they were gelded before reaching their prime. He also said it could help reduce diseases prevalent in quarter horses by enabling breeders to “silence detrimental genes.”

But many opponents within the AQHA say it would have the opposite effect.

“From a breeder’s standpoint … we try to continually further improvement of the American quarter horse through selective breeding: Pick the best sire, match him to the best mare to produce the best foal,” said Micah McKinney, an AQHA member who operates Reliance Ranches in Llano, Texas. “I think that copying what already has been done would be going backward in the progression toward a better breed.”

Art Caplan, head of the medical ethics division at New York University’s Langone Medical Center and an NBC News contributor, said opponents like McKinney are right to be concerned, but are unlikely to prevail in what he described as an “ethically complex” case.

“Cloning would be bad for the sport,” he said. “It produces too many dead and unhealthy animals and it would probably diminish interest due to narrowing the variety among competitor horses."

ViaGen, an Amarillo company that is a leader in commercial cloning, has cloned 167 horses using the technology developed in Scotland, in addition to other farm animals like cattle and pigs, CEO Blake Russell told NBC News.

Russell said he warns clients, who pay $165,000 for “a 60-day-old, veterinarian-examined foal,” not to expect clones to be snorting images of their progenitors, or to necessarily perform at the same level.

“Just because you have the genetic potential to reproduce that performance, there are a tremendous number of environmental variables,” he said. “Sometimes the reproduction of that environment is impossible and it’s often unknown what got a horse to that caliber of performance.”

That said, he hears all the time from clients that the horse clones bear “striking similarities” to the originals, both in physical appearance and temperament.

“I own a cloned stallion myself and it’s uncanny,” he said.

'They seem to know they are elite'

Veneklasen said the multiple clones of the great gelded thoroughbred jumper Gem Twist, AGA Horse of the Year in 1989 and silver-medalist in the 1988 Olympics, demonstrate the vitality of the recovered genetic lines.

“It’s been amazing,” he said. “… Every one of them is amazing. They seem to know that they are elite.”

Alan Meeker, CEO of a family-owned private equity company, is involved in the most ambitious horse cloning program to date: Duplicating polo horses for Adolpho Cambiaso, an Argentine widely considered the world’s best player in the sport.

Operating as Crestview Genetics, Meeker and partners Cambiaso and South American businessman Ernesto Gutierrez have cloned 56 horses through September, using eggs from famed polo horses like Cuartetera, Lapa and Small Person. By next year, Cambiaso expects to be riding his clone cadre in major competitions, Meeker said.

“The first clones are already being ridden and competing in lower-rung games,” said Meeker, who licensed the cloning technology from ViaGen. “So far so good. … What we’ve seen to date, the clones themselves are going to be just as good and maybe perhaps better than the originals.”

He, too, said the originals’ personalities “flow through” the clones.

“Every single clone of Lapa that we’ve done is just as mean and ornery as the original Lapa. And every clone of Cuartetera is just as sweet and docile as Cuartetera herself,” he said.

Meeker said he also has cloned a “famous thoroughbred stallion” that he would not identify. But he and other cloning proponents say they have no intention of trying to elbow their way into thoroughbred racing, which mandates that horses must be born as a result of “natural cover” -- actual mating -- to be included in its registry.

“They don’t allow embryo transfer, don’t allow artificial insemination. I respect that,” Meeker said. “But if for some reason one day they decide to do that, we’re here to help them.”

That seems unlikely to happen, given the unwavering opposition of the sport’s governing body, The Jockey Club.

“The Jockey Club, as an organization dedicated to the improvement of thoroughbred racing and breeding, believes that the short- and long-term welfare of the sport … and the thoroughbred breed are best served by the current rules,” Jockey Club spokesman Bob Curran said in a statement.

Veneklasen, the plaintiff in the AQHA lawsuit, said he has no problem with that, but that the quarter horse association chose a different path when it embraced artificial insemination in the 1960s and embryo transfers in 1980.

“If you have the technology, why would you stop?” he said. “All of those have been allowed and suddenly you put the brakes on one? Let’s take emotion out of it and look at the science. … It’s just another tool. It can be used positively or negatively.”